Psycopath

[brain_meat]

There is a woman attending her mother's funeral. Also attending the funeral is a man whom she has never seen before. The woman immediately falls in love with this man. The man leaves and the woman never sees him again. Several weeks later the woman is distressed because she has not been able to find the man, so she kills her sister. Why did she kill her sister?

If you respond with a certain answer, you are a psycopath.